The invention relates generally to intake and exhaust systems for internal combustion engines. More specifically, the invention relates to such intake systems which provide enhanced combustion efficiency by providing more complete mixing of the air and fuel in the fluid flowing through the intake passageway. The invention also more specifically relates to such exhaust systems which provide enhanced combustion efficiency by improving exhaust gas flow through the exhaust system.
In a conventional internal combustion engine""s intake system, the fluid flow which moves adjacent the walls of the intake passageway i.e., laminar fluid flow, typically includes a substantial amount of gasoline particles which are not atomized. Fuel that is not atomized does not readily combust. Thus, incomplete atomization of the fuel in the fluid flow hinders complete combustion of the fluid. This laminar flow consequently reduces the combustion efficiency of the engine. In addition, due to the frictional forces generated by contact of the fluid flow against the walls of the intake passageway and the difference in mass density between the gasoline molecules and air molecules the laminar fluid flow travels through the passageway at a slower velocity than the rest of the fluid flow. This difference in velocity additionally tends to hamper mixing of the gasoline particles with the air particles thereby further contributing to incomplete combustion of the fluid and reducing the efficiency of the engine.
Turbulence of the fluid flow passing through the intake passageway reduces laminar fluid flow and provides improved mixing of the air and fuel. Such benefits can be realized if turbulence is produced either in the air entering the carburetor (or fuel injection system), in the fluid passing through the intake manifold or intake runners or in the fluid passing through the intake ports or around the intake valves of the engine. Consequently, various devices and systems have been designed to produce such turbulence at various locations in the intake system.
Some prior art devices which are designed to produce turbulence in the air entering the fuel introduction subsystem include vanes which deflect the air passing thereagainst in order to impart a swirling motion to the air. Some such devices include a hub or central member to which the device vanes are attached. The central member provides rigidity to the vanes so that they do not absorb energy of deflection but rather transmit that energy back to the fluid. The central mender is typically streamlined in order to reduce obstruction of fluid flow and reduce negative pressure areas which would otherwise create undesired turbulence.
One of the primary disadvantages of prior art devices or systems that generate intake air turbulence is that they restrict air flow through the system. This undesirably reduces the maximum quantity of air and fuel that is delivered into the engine thereby reducing its maximum horsepower output. An example of a prior art device that generates swirling and also turbulence of the intake air is disclosed in U.S. Pat. No. 5,947,081 to Kim. The device disclosed includes vanes which have slits as well as concave and convex portions. The small concave and convex surface portions of the vanes deflect small portions of the air flow at relatively sharp angles of deflection. This high degree of deflection produces turbulence of the air stream. This turbulence includes collision of fluid flow molecules rather than a smooth blending or mixing of the fluid flow. Consequently, the collisions absorb energy thereby reducing the velocity of the fluid flow and consequently reducing fluid flow.
Another important disadvantage of some prior art devices is that they are difficult or expensive to mount in the engine system, some prior art devices such as that disclosed in U.S. Pat. No. 4,424,777 to Klomp require that they be installed around the intake valves necessitating that the purchaser disassemble the engine and have engine components suitably machined to adapt these components to the device. But, this is typically a time consuming and expensive endeavor rendering such devices impractical for many motor vehicle owners. Similarly, other prior art devices require that they be installed in the intake manifold or runner necessitating that the purchaser disassemble major components of the engine in order to install such devices. But, this is a time consuming endeavor also requiring a degree of mechanical skill rendering such devices impractical for many motor vehicle owners.
Designers of such prior art intake fluid turbulence generation systems have recognized that the effectiveness of such turbulence varies according to the engine throttle position. U.S. Pat. No. 4,424,598 to Tsutsumi discloses an automobile swirl producing system which is responsive to engine load and engine operating conditions. Basically, the Tsutsumi system uses a pivot shaft responsive to carburetor throttle valve position to alter the swirl produced in the combustion chamber. However, the disadvantage of such a system is that it is difficult to properly install.
Designers of exhaust systems have also recognized that improving the effectiveness of exhaust gas flow out of the engine can provide improved combustion efficiency. There have consequently been many exhaust systems that have sought to increase the velocity of exhaust gas flow out of the exhaust system and thereby scavenge exhaust gases from the combustion chamber and exhaust ports. Some exhaust header systems have been designed to position exhaust pipes around the inner circumference of a collector pipe to produce swirling of the exhaust gases from the collector pipe in a vortex flow and thereby enhance exhaust gas flow therefrom. Such systems have been very effective in improving exhaust as well as intake fluid flow and thereby improving combustion. However, such systems require retuning of the engine and replacement of major engine system components and are thus impractical for many motor vehicle owners.
The many requirements for such air swirling or air turbulence generating devices and systems have resulted in prior art systems and devices in which there are compromises between swirl or turbulence generating effectiveness and air flow restriction. In addition, there have also been many prior art systems that have been very effective in generating the required swirl or turbulence yet have necessitated undue engine component alterations and labor consumption. Consequently, what is needed is an intake and exhaust fluid swirling device which does not require special tools for installation and thus may be easily manually installed. What is also needed is an intake and exhaust fluid swirling device providing enhanced swirl generation while producing minimal fluid flow restriction.
It is a principal object of the present invention to provide an air swirling device that can be positioned in the intake passageway for air entering the fuel introduction subsystem of an internal combustion engine.
It is another object of the present invention to provide an intake and exhaust fluid swirling device having structural components that are angled and shaped to provide enhanced swirling of the fluid flow.
It is another object of the present invention to provide an intake and exhaust fluid swirling device having minimal structural components to provide minimal restriction of fluid flow therethrough.
It is also an object of the present invention to provide an intake and exhaust fluid swirling device having structural components that are shaped to provide minimal restriction of fluid flow therethrough.
It is also an object of the present invention to provide an air swirling device that does not require disassembly of major engine components for installation thereof.
It is an object of the present invention to provide an air swirling device that may be manually installed in an intake air passageway of an internal combustion engine.
It is an object of the present invention to provide an air swirling device that is structurally resilient to provide a snug fit in an intake air passageway of an internal combustion engine.
It is an object of the present invention to provide an exhaust gas swirling device that reduces back pressure.
Essentially, the device of the present invention is designed to be positioned in the fluid flow path of an internal combustion engine and deflect the flow passing therethrough so as to impart a rotational or swirling type of movement to the fluid. This swirling movement tends to move the fluid away from the walls of the passageway and reduce continual contact with the walls of the passageway which produce frictional forces exerting a drag on the fluid flow. When positioned in an intake passageways the swirl provides enhanced mixing of the air and fuel yielding more complete combustion of the fuel mixture. When positioned in a tailpipe or exhaust pipe, the swirl reduces the decrease in exhaust gas velocity that would otherwise occur yielding reduced backpressure and thereby increasing engine power output.
The device achieves its goal of swirling the fluid flow by incorporating vanes which are positioned in the fluid flow stream. The vanes are angled so that they deflect the fluid laterally into a rotational movement.
The device includes a housing within which the vanes are mounted. The housing is open at both longitudinal ends for the fluid flow to pass through. The housing is sized and shaped to accommodate the intake ducts or passageways of various motor vehicles as well as the exhaust pipes of various motor vehicles. This makes it relatively easy for a user to singly manually insert the device into an intake duct or exhaust pipe where it snugly fits therein and stays in place without the need for attachment means to anchor it in place.
The vanes are specially curved (at their edges) and shaped for maximal efficiency in producing the swirl effect with minimal fluid flow restriction. The vanes are longitudinally longer at the inner periphery of the housing than at the central area of the housing. Thus, the peripheral portions of the vanes are larger and therefore provide more deflection than the smaller more central portions of the vanes. This is desirable because it more efficiently yields the desired swirl. This is because the swirl produced is essentially air rotation about a central axis with the more peripheral air at peripheral areas of the passageway rotating more than the air at more centrally located areas. Consequently, flow deflection at the peripheral portions of the housing is much more effective in producing the desired fluid rotation about the central axis of the housing. Similarly, near the central area of the housing the vane portions are smaller producing less deflection and concomitantly less fluid flow restriction at the housing area where swirl can less effectively be produced.
The lower or trailing edges of the vanes are also curved to streamline the vanes for reduced fluid flow resistance. The curvature is in a direction of from the periphery to the center of the housing. Since the peripheral ends of the primary vanes are longer than the central (or inner) ends, the lower or trailing edge is angled in the direction of fluid flow and the curvature thereof is also curved in this direction.
In addition, the lower end portions and lower medial end portions of the vanes are bent in the direction of the deflection of the fluid flow. The lower end portions and lower medial end portions are thus angled laterally to enhance deflection of the fluid flow. This deflection provided by these lower portions is also very effective because the fluid flow has been previously deflected by upper portions of the primary vanes and has been moving downwardly alongside the vanes until it reaches these lower portions where it is further deflected to add more lateral movement and thereby more rotational movement to the fluid flow.
The device also includes secondary vanes for maximal efficiency in producing the swirl effect with minimal fluid flow restriction. The secondary vanes are mounted in the housing and attached to the walls thereof. The secondary vanes are also angled the same as the primary vanes for producing the desired deflection of the fluid flow. But, the secondary vanes are shorter in width and thus extend only a short distance toward the center and into the inner area of the housing so that they are located only in the inner peripheral area of the housing where there is maximal effectiveness in producing the fluid flow rotational movement.
Although prior art swirl devices utilize a central member or hub to which the vanes are attached, the present invention obviates the need for such a central member by interconnecting lateral inner ends of the vanes at the central area of the device. The central area of the housing is thus open and there is thus nothing to impede fluid flow through the center of the device. Thus, the present invention provides improved airflow over prior art comparable devices. Moreover, elimination of a central member does not result in reduction in the efficiency of the device in producing air swirl because the swirl produced is essentially air rotation about a central axis i.e., the center of the housing, with the more peripheral air at peripheral areas of the passageway rotating more than the air at more centrally located areas. The overall fluid movement is thus in the shape of a spiral as it moves through the passageway. Consequently, the swirl cannot typically be effectively accomplished by means of structures located at the center of the device but can instead be effectively accomplished by means of structures located at more peripheral portions of the device. Indeed, maximal twisting or turning of the fluid flow is accomplished by means of structures such as the secondary vanes and structure portions such as the larger peripheral portions of the primary vanes both of which are located at the area of the inner perimeter of the device.